Engine On-Vehicle Inspection

Warm up the engine and stop the engine.

NOTICE:

A warmed up engine should have an engine coolant temperature of over 80°C (176°F), have an engine oil temperature of 60°C (140°F), and the engine rpm should be stabilized.

When using the intelligent tester:

1. Connect the intelligent tester to the DLC3.
   

2. Start the engine and idle it.
   

3. Push the intelligent tester main switch ON.
   

4. Enter the following items: Powertrain / Engine and ECT / Data list / IGN Advance.
   

   Ignition timing:

   8 to 12° BTDC @ idle (Shift lever on N)
   

   HINT:

   Please refer to the intelligent tester operator's manual for further details.

Warm up the engine.

NOTICE:

A warmed up engine should have an engine coolant temperature of over 80°C (176°F) and an engine oil temperature of 60°C (140°F), and the engine rpm should be stabilized.

When using the intelligent tester:

1. Connect the intelligent tester to the DLC3.
   

   NOTICE:

   Switch off all accessories and A/C before connecting the intelligent tester.

2. Rev the engine at 2,500 rpm for approximately 90 seconds.
   

3. Push the intelligent tester main switch ON.
   

4. Enter the following items: Powertrain / Engine and ECT / Data list / Engine SPD.
   

   Idle speed:

   700 to 800 rpm
   

   NOTICE:

   When checking the idle speed, the transmission should be in neutral.

   HINT:

   Please refer to the intelligent tester operator's manual for further details.

   If the idle speed is not as specified, check the air intake system.
   

Remove the V-bank cover.

Remove the air cleaner inlet and intake air pipe.

Disconnect the throttle control motor connector.

Remove the oil level gauge guide.

Remove the 8 ignition coils.

Remove the 8 spark plugs.

Disconnect the 8 injector connectors.

Check the cylinder compression pressure.

1. Insert a compression gauge into the spark plug hole.
   

2. Fully open the throttle.
   

3. While cranking the engine, measure the compression pressure.
   

   Compression pressure:

   1,226 kPa (12.5 kgf/cm2, 178 psi) or more
   

   Minimum pressure:

   981 kPa (10.0 kgf/cm2, 142 psi)
   

   Difference between each cylinder:

   98 kPa (1.0 kgf/cm2, 14 psi)
   

   NOTICE:

   1. Always use a fully charged battery to obtain an engine speed of 250 rpm or more.
      
   2. Check the other cylinder's compression pressure in the same way.
      
   3. This measurement must be done as quickly as possible.
      
   If the cylinder compression is low, pour a small amount of engine oil into the cylinder through the spark plug hole and inspect again.
   

   HINT:

   If adding oil increases the compression, the piston rings and/or cylinder bore may be worn or damaged.

   If pressure stays low, a valve may be stuck or seated improperly, or there may be leakage in the gasket.
   

Connect the 8 injector connectors.

Install the 8 spark plugs.

Install the 8 ignition coils.

Install the oil level gauge guide.

Connect the throttle control motor connector.

Install the air cleaner inlet and intake air pipe.

Install the V-bank cover.

Start the engine.

Rev the engine at 2,500 rpm for approximately 180 seconds.

Insert a CO/HC meter testing probe at least 40 cm (1.3 ft.) into the tailpipe during idling.

Check CO/HC concentration at idle and/or 2,500 rpm.

HINT:

1. Complete the measurement within 3 minutes.
   
2. Check regulations in your area when performing 2 mode CO/HC concentration testing (engine check at both idle speed and at 2,500 rpm).
   

If the CO/HC concentration does not comply with regulations, perform troubleshooting in the order given below.

1. Check the heated oxygen sensor operation (Click here).
   

2. See the table below for possible causes, and then inspect and repair.
   
   

   CO	HC	Symptom	Causes
   Normal	High	Rough idle	1. Faulty ignitions: Incorrect timing Fouled, shorted or improperly gapped plugs. 2. Incorrect valve clearance 3. Leaky intake and exhaust valves 4. Leaky cylinder
   Low	High	Rough idle (fluctuating HC reading)	1. Vacuum leaks: PCV hose Intake manifold Throttle body 2. Lean mixture causing misfire
   High	High	Rough idle (black smoke from exhaust)	1. Restricted air filter 2. Faulty SFI system: Faulty pressure regulator Defective ECT sensor Faulty ECM Faulty injector Faulty throttle position sensor MAF sensor